A back contact solar cell and a preparation method thereof

Abstract

The application discloses a kind of double potential barrier quantum trap TOPCon solar cell without explosion film and preparation method thereof, it is related to solar cell manufacturing technical field, the structure of this solar cell is in order from top to bottom front surface SiN x Anti-reflection layer, AlO x Passivation layer, boron emitter, silicon base, first layer tunneling oxide layer, first layer Poly-Si layer, second layer tunneling oxide layer, second layer Poly-Si layer, back surface SiN x Anti-reflection layer; the upper side of the solar cell is also connected with selective boron emitter, and the lower side is also connected with metal electrode. This double potential barrier quantum trap passivation contact structure not only can reduce the generation of explosion film phenomenon, but also can effectively improve the back passivation effect, improve short-circuit current and improve cell efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of solar cell manufacturing, and in particular to a non-explosive film double-barrier quantum trap TOPCon solar cell and a preparation method thereof. Background Art

[0002] TOPCon (Tunneling Oxide Passivated Contact) solar cells are a type of cell that consists of tunneling oxide and heavily doped polysilicon as passivating contacts. There are three main preparation methods: LPCVD (low pressure chemical vapor deposition), PECVD (plasma enhanced chemical vapor deposition) and PVD (magnetron sputtering). Among them, PECVD has the advantages of single-sided preparation and high efficiency, and is an important technical means for preparing TOPCon solar cells. However, PECVD deposition of n + -a-Si:H (N-type hydrogenated amorphous silicon), during high temperature annealing, due to n + -a-Si:H to n + -The conversion of Poly-Si (N-type polysilicon) is accompanied by the release of a large amount of hydrogen, which can lead to film explosion problems.

[0003] Currently, p + -Poly-Si (P-type polysilicon) has attracted much attention, but its film explosion phenomenon is more serious, which is the main constraint of p-type polysilicon. + -An important factor in the development of Poly-Si TOPCon batteries.

[0004] Double-barrier quantum-trapped TOPCon solar cells have also attracted considerable attention. They inhibit the deep diffusion of phosphorus atoms and optimize the band structure, providing enhanced passivation, reducing recombination current density and improving solar cell efficiency. However, current PECVD technology for fabricating boron-doped double-barrier quantum-trapped TOPCon solar cells still suffers from film bursting, and the process is also very complex. Summary of the Invention

[0005] Based on the problems existing in the background technology, the purpose of the present invention is to provide a double-barrier quantum trap TOPCon solar cell without film explosion and a preparation method thereof. This double-barrier quantum trap passivation contact structure can not only reduce the occurrence of film explosion, but also effectively improve the back passivation effect, increase the short-circuit current, and enhance the battery efficiency.

[0006] The present invention is achieved through the following technical solutions:

[0007] In the first aspect, the present application provides a non-explosive film double barrier quantum trap TOPCon solar cell, the structure of the solar cell is from top to bottom: the front surface SiN x Anti-reflection layer, AlO xPassivation layer, boron emitter, silicon substrate, first tunneling oxide layer, first Poly-Si layer, second tunneling oxide layer, second Poly-Si layer, back surface SiN x Anti-reflection layer; the solar cell is also connected to a selective boron emitter on the top and a metal electrode on the bottom.

[0008] In a second aspect, the present application provides a method for preparing a non-explosive film double-barrier quantum trap TOPCon solar cell, comprising the following steps:

[0009] Step a: Boron diffusion is performed on an alkali-textured N-type Si substrate, followed by local heavy doping of the front side of the silicon wafer. The silicon wafer is then oxidized and repaired in a post-oxidation process to repair any damage, while also deepening the PN junction.

[0010] Step b: removing the borosilicate glass on the back and edge of the silicon wafer, and then polishing the back of the silicon wafer;

[0011] Step c: A tunneling oxide layer is formed on the silicon wafer, followed by the deposition of an in-situ doped a-Si:H layer. The excess hydrogen inside the a-Si is released in advance through a high-temperature heating process (600°C to 1000°C). Then, a tunneling oxide layer and an in-situ doped a-Si:H layer are deposited in sequence. The a-Si is crystallized into poly-Si through a high-temperature annealing process, and phosphorus atoms are activated to form a double-barrier quantum trap passivation structure.

[0012] Step d: After annealing, the silicon wafer is chain-dephosphorized and then RCA cleaned to etch away the front Poly-Si and then the front SiN x / AlO x Deposition and backside SiN x sedimentation;

[0013] Step e: After screen printing, sintering and light injection on the silicon wafer, a film-blast-free double-barrier quantum trap TOPCon solar cell can be produced.

[0014] The present invention prepares Poly-Si through a two-step deposition method. First, a first thin layer of a-Si:H is deposited. The hydrogen in the first thin layer of a-Si:H is released in advance through high-temperature heating, and then a second layer of a-Si:H is deposited (ensuring that the total thickness of the two deposited a-Si:H layers is approximately 120nm). Because the high-temperature hydrogen release process preemptively releases the hydrogen in the first thin layer of a-Si:H, the amount of underlying hydrogen released during the high-temperature annealing process when a-Si:H is converted to Poly-Si is greatly reduced. Therefore, the film explosion problem is improved, greatly reducing the probability of film explosion. In addition, the second tunneling oxide layer has the function of blocking hydrogen release, similarly suppressing internal hydrogen release, greatly reducing the impact of internal hydrogen release on film quality. Furthermore, the thickness of the Poly-Si can also meet the production requirements of solar cells. The double-barrier quantum trap TOPCon solar cell, which has high-temperature hydrogen release and is prepared by a two-step deposition method, not only solves the problem of boron-doped polysilicon easily exploding due to hydrogen release, but also greatly improves the passivation performance of the back of the battery, optimizes the energy band structure of the battery, reduces the composite current density, inhibits the deep diffusion of phosphorus atoms, increases the short-circuit current, and improves the efficiency of the battery cell.

[0015] Furthermore, in step a, a laser doping method is used to locally re-dope the front side of the silicon wafer.

[0016] Furthermore, in step b, acid is used to remove the borosilicate glass on the back and edge of the silicon wafer.

[0017] Furthermore, the acid includes hydrofluoric acid.

[0018] Furthermore, in step b, the back side of the silicon wafer is polished by alkaline etching.

[0019] Furthermore, the alkali used in the alkali etching is potassium hydroxide.

[0020] Furthermore, the method for preparing the tunneling oxide layer in step c is N2O plasma assisted oxidation.

[0021] Furthermore, in step c, PECVD is used to deposit in-situ doped a-Si.

[0022] Furthermore, the total thickness of the two a-Si:H layers deposited in step c is 110 nm to 130 nm.

[0023] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0024] This invention deposits TOPCon solar cells using a two-step deposition method, incorporating a high-temperature hydrogen release process during the deposition process. This effectively reduces hydrogen release from the underlying layer, minimizing film bursting and improving the quality of the TOPCon passivation layer via the PECVD route. Furthermore, utilizing the step-by-step deposition principle of double-barrier quantum-trapped TOPCon solar cells, a high-temperature hydrogen release process is added after the first layer of a-Si / SiOx is deposited to reduce hydrogen release during the high-temperature annealing process. This double-barrier quantum-trapped passivation contact structure not only reduces film bursting but also effectively improves backside passivation, increasing short-circuit current and boosting cell efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the following briefly introduces the drawings required for use in the examples. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be considered as limiting the scope. A person of ordinary skill in the art can also derive other relevant drawings based on these drawings without inventive effort. In the drawings:

[0026] Figure 1 This is a schematic structural diagram of a non-explosive film double-barrier quantum trap TOPCon solar cell in the present invention.

[0027] 1-Front surface SiN x Antireflection layer, 2-AlO x Passivation layer, 3-boron emitter, 4-selective boron emitter, 5-silicon substrate, 6-first tunneling oxide layer, 7-first Poly-Si layer, 8-second tunneling oxide layer, 9-second Poly-Si layer, 10-back surface SiN x Anti-reflection layer, 11-metal electrode. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0029] The following describes, with appropriate reference to the accompanying drawings, embodiments of the solar cell and its manufacturing method disclosed herein. However, unnecessary detailed descriptions may be omitted. For example, detailed descriptions of well-known matters and repeated descriptions of substantially identical structures may be omitted. This is to avoid unnecessarily lengthy descriptions and to facilitate understanding by those skilled in the art. Furthermore, the drawings and the following description are provided to enable those skilled in the art to fully understand the present application and are not intended to limit the subject matter described in the claims.

[0030] The "ranges" disclosed herein are defined in terms of lower and upper limits, where a given range is defined by selecting a lower limit and an upper limit, and the selected lower and upper limits define the boundaries of the particular range. Ranges defined in this manner can be inclusive or exclusive of the end values ​​and can be combined arbitrarily, i.e., any lower limit can be combined with any upper limit to form a range. For example, if ranges of 60 to 120 and 80 to 110 are listed for a particular parameter, it is understood that ranges of 60 to 110 and 80 to 120 are also contemplated. Furthermore, if minimum range values ​​of 1 and 2 are listed, and if maximum range values ​​of 3, 4, and 5 are listed, the following ranges are all contemplated: 1 to 3, 1 to 4, 1 to 5, 2 to 3, 2 to 4, and 2 to 5. In this application, unless otherwise indicated, the numerical range "a to b" is a shorthand representation of any combination of real numbers between a and b, where a and b are both real numbers. For example, a numerical range of "0-5" indicates that all real numbers between "0-5" are listed herein, and "0-5" is simply an abbreviation for these numerical combinations. Furthermore, when a parameter is expressed as an integer ≥ 2, this is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0031] Unless otherwise specified, all embodiments and optional embodiments of the present application can be combined with each other to form a new technical solution.

[0032] Unless otherwise specified, all technical features and optional technical features of this application can be combined with each other to form a new technical solution.

[0033] Unless otherwise specified, all steps of the present application may be performed sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), indicating that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially. For example, the method may further include step (c), indicating that step (c) may be added to the method in any order, for example, the method may include steps (a), (b) and (c), or may include steps (a), (c) and (b), or may include steps (c), (a) and (b), etc.

[0034] Unless otherwise specified, the terms "include" and "comprising" used in this application may be open-ended or closed-ended. For example, "include" and "comprising" may mean that other components not listed may also be included or that only the listed components are included.

[0035] Example 1

[0036] This embodiment provides a non-explosive film double barrier quantum trap TOPCon solar cell and its preparation method, such as Figure 1 As shown, the structure of the solar cell is from top to bottom: front surface SiN x Anti-reflection layer 1, AlO x Passivation layer 2, boron emitter 3, silicon substrate 5, first tunneling oxide layer 6, first Poly-Si layer 7, second tunneling oxide layer 8, second Poly-Si layer 9, back surface SiN x The anti-reflection layer 10; the solar cell is also connected to a selective boron emitter 4 on the top and a metal electrode 11 on the bottom.

[0037] The preparation method of the above solar cell is as follows:

[0038] S1: Boron diffusion is performed on the alkali-textured N-type Si substrate, and then the front side of the silicon wafer is locally heavily doped using laser doping technology. Then, in the post-oxidation process, the damage caused by the laser is repaired by oxidation and the PN junction is deeply pushed;

[0039] S2: Remove the BSG (borosilicate glass) on the back and edge by HF, and then polish the back of the silicon wafer by alkaline etching;

[0040] S3: Prepare a tunnel oxide layer (SiO x ), followed by the PECVD technology to deposit the in-situ doped a-Si (amorphous silicon) structure; through the high-temperature heating process, the excess hydrogen inside the a-Si is released in advance to avoid the subsequent excessive release of hydrogen causing the film to explode, and then a layer of SiO is deposited in sequence x and in-situ doping of a-Si (amorphous silicon); through a high-temperature annealing process, the a-Si is crystallized into Poly-Si and phosphorus atoms are activated to form a double-barrier quantum trap passivation structure. At the same time, due to the early high-temperature hydrogen release, only a small amount of hydrogen is released during the annealing process, effectively reducing the occurrence of film explosion sites; the total thickness of the two layers of a-Si (amorphous silicon) is 120nm, the thickness of the first layer of a-Si (amorphous silicon) is 30nm, and the thickness of the second layer of a-Si (amorphous silicon) is 90nm;

[0041] S4: After annealing, the silicon wafer is chain-deposited with PSG (phosphorus silicon glass), and then RCA cleaning is performed to etch away the Poly-Si on the front side; then the front SiN x / AlO x Deposition and backside SiN x sedimentation;

[0042] S5: Screen printing, sintering and light injection are performed on silicon wafers to produce explosion-free double-barrier quantum trap TOPCon solar cells.

[0043] Example 2

[0044] This embodiment provides a non-explosive film double-barrier quantum trap TOPCon solar cell and a method for preparing the same. Unlike Example 1, the total thickness of the two a-Si (amorphous silicon) layers is 120 nm, with the first a-Si (amorphous silicon) layer having a thickness of 40 nm and the second a-Si (amorphous silicon) layer having a thickness of 80 nm. Other technical features are identical to those of Example 1.

[0045] The structure of the solar cell is from top to bottom: the front surface SiN x Anti-reflection layer, AlO x Passivation layer, boron emitter, silicon substrate, first tunneling oxide layer, first Poly-Si layer, second tunneling oxide layer, second Poly-Si layer, back surface SiN x Anti-reflection layer; the solar cell is also connected to a selective boron emitter on the top and a metal electrode on the bottom.

[0046] The preparation method of the above solar cell is as follows:

[0047] S1: Boron diffusion is performed on the alkali-textured N-type Si substrate, and then the front side of the silicon wafer is locally heavily doped using laser doping technology. Then, in the post-oxidation process, the damage caused by the laser is repaired by oxidation and the PN junction is deeply pushed;

[0048] S2: Remove the BSG (borosilicate glass) on the back and edge by HF, and then polish the back of the silicon wafer by alkaline etching;

[0049] S3: Prepare a tunnel oxide layer (SiO x ), followed by the PECVD technology to deposit the in-situ doped a-Si (amorphous silicon) structure; through the high-temperature heating process, the excess hydrogen inside the a-Si is released in advance to avoid the subsequent excessive release of hydrogen causing the film to explode, and then a layer of SiO is deposited in sequence x and in-situ doping of a-Si (amorphous silicon); through a high-temperature annealing process, the a-Si is crystallized into Poly-Si and phosphorus atoms are activated to form a double-barrier quantum trap passivation structure. At the same time, due to the early high-temperature hydrogen release, only a small amount of hydrogen is released during the annealing process, effectively reducing the occurrence of film explosion sites; the total thickness of the two layers of a-Si (amorphous silicon) is 120nm, the thickness of the first layer of a-Si (amorphous silicon) is 40nm, and the thickness of the second layer of a-Si (amorphous silicon) is 80nm;

[0050] S4: After annealing, the silicon wafer is chain-deposited with PSG (phosphorus silicon glass), and then RCA cleaning is performed to etch away the Poly-Si on the front side; then the front SiN x / AlO x Deposition and backside SiN x sedimentation;

[0051] S5: Screen printing, sintering and light injection are performed on silicon wafers to produce explosion-free double-barrier quantum trap TOPCon solar cells.

[0052] Example 3

[0053] This embodiment provides a non-explosive film double-barrier quantum trap TOPCon solar cell and a preparation method thereof. The difference from Example 1 is that the total thickness of the two layers of a-Si (amorphous silicon) is 120nm, the thickness of the first layer of a-Si (amorphous silicon) is 60nm, and the thickness of the second layer of a-Si (amorphous silicon) is 60nm.

[0054] The structure of the solar cell is from top to bottom: the front surface SiN x Anti-reflection layer, AlO x Passivation layer, boron emitter, silicon substrate, first tunneling oxide layer, first Poly-Si layer, second tunneling oxide layer, second Poly-Si layer, back surface SiN x Anti-reflection layer; the solar cell is also connected to a selective boron emitter on the top and a metal electrode on the bottom.

[0055] The preparation method of the above solar cell is as follows:

[0056] S1: Boron diffusion is performed on the alkali-textured N-type Si substrate, and then the front side of the silicon wafer is locally heavily doped using laser doping technology. Then, in the post-oxidation process, the damage caused by the laser is repaired by oxidation and the PN junction is deeply pushed;

[0057] S2: Remove the BSG (borosilicate glass) on the back and edge by HF, and then polish the back of the silicon wafer by alkaline etching;

[0058] S3: Prepare a tunnel oxide layer (SiO x ), followed by the PECVD technology to deposit the in-situ doped a-Si (amorphous silicon) structure; through the high-temperature heating process, the excess hydrogen inside the a-Si is released in advance to avoid the subsequent excessive release of hydrogen causing the film to explode, and then a layer of SiO is deposited in sequence xand in-situ doping of a-Si (amorphous silicon); through a high-temperature annealing process, the a-Si is crystallized into Poly-Si at high temperature, and phosphorus atoms are activated to form a double-barrier quantum trap passivation structure. At the same time, due to the early high-temperature hydrogen release, only a small amount of hydrogen is released during the annealing process, effectively reducing the occurrence of film explosion sites; the total thickness of the two layers of a-Si (amorphous silicon) is 120nm, the thickness of the first layer of a-Si (amorphous silicon) is 60nm, and the thickness of the second layer of a-Si (amorphous silicon) is 60nm;

[0059] S4: After annealing, the silicon wafer is chain-deposited with PSG (phosphorus silicon glass), and then RCA cleaning is performed to etch away the Poly-Si on the front side; then the front SiN x / AlO x Deposition and backside SiN x sedimentation;

[0060] S5: Screen printing, sintering and light injection are performed on silicon wafers to produce explosion-free double-barrier quantum trap TOPCon solar cells.

[0061] The explosion-free double barrier quantum trap TOPCon solar cell prepared by the preparation method of Example 1, Example 2 and Example 3 adopts a step-by-step deposition method. x After deposition, a high-temperature hydrogen release process is added to release the hydrogen in the bottom a-Si in advance, and then a layer of a-Si / SiO is deposited. x During high-temperature annealing, the excess hydrogen in the underlying a-Si has been released in advance, so the film bursting phenomenon caused by hydrogen release is greatly reduced. This not only reduces the occurrence of film bursting, but also improves the quality of the TOPCon passivation layer on the PECVD route, increases the short-circuit current, and improves battery efficiency.

[0062] Comparative Example 1

[0063] This comparative example provides a double-barrier quantum trap TOPCon solar cell and its preparation method. Unlike Example 1, this comparative example does not include a high-temperature hydrogen release process during the deposition of a-Si (amorphous silicon). Other technical features are identical to those of Example 1.

[0064] The structure of the solar cell is from top to bottom: the front surface SiN x Anti-reflection layer, AlO x Passivation layer, boron emitter, silicon substrate, first tunneling oxide layer, first Poly-Si layer, second tunneling oxide layer, second Poly-Si layer, back surface SiN x Anti-reflection layer; the solar cell is also connected to a selective boron emitter on the top and a metal electrode on the bottom.

[0065] The preparation method of the above solar cell is as follows:

[0066] S1: Boron diffusion is performed on the alkali-textured N-type Si substrate, and then the front side of the silicon wafer is locally heavily doped using laser doping technology. Then, in the post-oxidation process, the damage caused by the laser is repaired by oxidation and the PN junction is deeply pushed;

[0067] S2: Remove the BSG (borosilicate glass) on the back and edge by HF, and then polish the back of the silicon wafer by alkaline etching;

[0068] S3: Prepare a tunnel oxide layer (SiO x ), followed by the PECVD technique to deposit an in-situ doped a-Si (amorphous silicon) structure; and then depositing a layer of SiO x and in-situ doped a-Si (amorphous silicon); wherein the total thickness of the two a-Si (amorphous silicon) layers is 120 nm, the thickness of the first a-Si (amorphous silicon) layer is 30 nm, and the thickness of the second a-Si (amorphous silicon) layer is 90 nm;

[0069] S4: After annealing, the silicon wafer is chain-deposited with PSG (phosphorus silicon glass), and then RCA cleaning is performed to etch away the Poly-Si on the front side; then the front SiN x / AlO x Deposition and backside SiN x sedimentation;

[0070] S5: Screen printing, sintering and light injection are performed on silicon wafers to produce explosion-free double-barrier quantum trap TOPCon solar cells.

[0071] Comparative Example 2

[0072] This comparative example provides a method for preparing a TOPCon solar cell. Different from Example 1, the solar cell in this example is prepared by a one-step deposition method.

[0073] The preparation method is:

[0074] S1: Boron diffusion is performed on the alkali-textured N-type Si substrate, and then the front side of the silicon wafer is locally heavily doped using laser doping technology. Then, in the post-oxidation process, the damage caused by the laser is repaired by oxidation and the PN junction is deeply pushed;

[0075] S2: Remove the BSG (borosilicate glass) on the back and edge by HF, and then polish the back of the silicon wafer by alkaline etching;

[0076] S3: Prepare a tunnel oxide layer (SiO x), followed by depositing a 120nm thick in-situ doped a-Si (amorphous silicon) structural layer using PECVD technology;

[0077] S4: After annealing, the silicon wafer is chain-deposited with PSG (phosphorus silicon glass), and then RCA cleaning is performed to etch away the Poly-Si on the front side; then the front SiN x / AlO x Deposition and backside SiN x sedimentation;

[0078] S5: Screen printing, sintering and light injection are performed on silicon wafers to produce explosion-free double-barrier quantum trap TOPCon solar cells.

[0079] The performance of the solar cells prepared by the methods of Example 1, Example 2, Example 3, Comparative Example 1, and Comparative Example 2 were tested, and the test results are shown in the following table.

[0080]

[0081] It can be seen from the data in the table that, compared with Examples 1 to 3, the solar cells prepared by the methods of Comparative Examples 1 and 2 have serious film explosion phenomena and low cell efficiency.

[0082] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for preparing a non-explosive film double barrier quantum trap TOPCon solar cell, characterized in that: The following steps are involved: Step a: Boron diffusion is performed on an alkali-textured N-type Si substrate, followed by local heavy doping of the front side of the silicon wafer. The silicon wafer is then oxidized and repaired in a post-oxidation process to repair any damage, while also deepening the PN junction. Step b: removing the borosilicate glass on the back and edge of the silicon wafer, and then polishing the back of the silicon wafer; Step c: forming a tunneling oxide layer on the silicon wafer, followed by depositing an in-situ doped a-Si:H layer, then using a high-temperature heating process to release excess hydrogen in the a-Si in advance, and then sequentially depositing a tunneling oxide layer and an in-situ doped a-Si:H layer. Then, using a high-temperature annealing process, the a-Si is crystallized into poly-Si and phosphorus atoms are activated to form a double-barrier quantum trap passivation structure; wherein the high-temperature heating process is performed at a process temperature of 1000°C; Step d: After annealing, the silicon wafer is chain-dephosphorized and then RCA cleaned to etch away the front Poly-Si and then the front SiN x / AlO x Deposition and backside SiN x sedimentation; Step e: After screen printing, sintering and light injection on the silicon wafer, a non-explosive film double-barrier quantum trap TOPCon solar cell can be produced; The total thickness of the two a-Si:H layers deposited in step c is 120 nm; specifically, the thickness of the first a-Si amorphous silicon layer is 30 nm, and the thickness of the second a-Si amorphous silicon layer is 90 nm; or the thickness of the first a-Si amorphous silicon layer is 40 nm, and the thickness of the second a-Si amorphous silicon layer is 80 nm; or the thickness of the first a-Si amorphous silicon layer is 60 nm, and the thickness of the second a-Si amorphous silicon layer is 60 nm; The structure of the solar cell is as follows from top to bottom: the front surface SiN x Anti-reflection layer, AlO x Passivation layer, boron emitter, silicon substrate, first tunneling oxide layer, first Poly-Si layer, second tunneling oxide layer, second Poly-Si layer, back surface SiN x Anti-reflection layer; the solar cell is also connected to a selective boron emitter on the top and a metal electrode on the bottom.

2. The method for preparing a non-explosive film double barrier quantum trap TOPCon solar cell according to claim 1, characterized in that: In step a, laser doping is used to locally re-dope the front side of the silicon wafer.

3. The method for preparing a non-explosive film double barrier quantum trap TOPCon solar cell according to claim 1, characterized in that: In step b, acid is used to remove the borosilicate glass on the back and edges of the silicon wafer.

4. The method for preparing a non-explosive film double barrier quantum trap TOPCon solar cell according to claim 3, characterized in that: The acid includes hydrofluoric acid.

5. The method for preparing a non-explosive film double barrier quantum trap TOPCon solar cell according to claim 1, characterized in that: In step b, the back side of the silicon wafer is polished by alkaline etching.

6. The method for preparing a non-explosive film double barrier quantum trap TOPCon solar cell according to claim 5, characterized in that: The alkali used in alkaline etching is potassium hydroxide.

7. The method for preparing a non-explosive film double barrier quantum trap TOPCon solar cell according to claim 1, characterized in that: The method for preparing the tunneling oxide layer in step c is N2O plasma assisted oxidation.

8. The method for preparing a non-explosive film double barrier quantum trap TOPCon solar cell according to claim 1, characterized in that: In step c, the PECVD method is used to deposit in-situ doped a-Si.

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